Ball Screws Actuators

Linear Actuators and Motors Selection Guidelines

Actuator is a mechanical device for moving or controlling a mechanism or system. It is operated by a source of energy, usually in the form of an electric current, hydraulic fluid pressure or pneumatic pressure, and converts that energy into some kind of motion. Linear actuator is an actuator that creates linear motion, whereas rotary actuator creates rotary motion. Mechanical and hydraulic actuation are the most common methods of achieving the linear motion. Many linear actuators are driven by a non-linear motion.

Types of Linear Actuators Mechanical Linear Actuators – Mechanical linear actuators typically operate by conversion of rotary motion into linear motion. Conversion is commonly made via a few simple types of mechanisms:

Screw Actuators : Screw jack, ball screw and roller screw actuators all operate on the principle of the simple machine known as the screw. By rotating the actuator’s nut, the screw shaft moves in a line. Wheel and Axle Actuators : Hoist, winch, rack and pinion, chain drive, belt drive, rigid chain and rigid belt actuators operate on the principle of the wheel and axle. By rotating a wheel/axle (e.g. drum, gear, pulley or shaft) a linear member (e.g. cable, rack, chain or belt) moves. Cam Actuators : Cam actuators function on a principle similar to that of the wedge, but provide relatively limited travel. As a wheel-like cam rotates, its eccentric shape provides thrust at the base of a shaft. Hydraulic Actuators – Hydraulic actuators or hydraulic cylinders typically involve a hollow cylinder having a piston inserted in it. The two sides of the piston are alternately pressurized/de-pressurized to achieve controlled precise linear displacement of the piston and in turn the entity connected to the piston. The physical linear displacement is only along the axis of the piston/cylinder. Pneumatic Actuators – Pneumatic actuators, or pneumatic cylinders, are similar to hydraulic actuators except they use compressed gas to provide pressure instead of a liquid. Piezoelectric Actuators – The piezoelectric effect is a property of certain materials in which application of a voltage to the material causes it to expand. Very high voltages correspond to only tiny expansions.

Ball Screws & Actuators Co, catalog no. 94 : ball screws, acme screws, actuators, linear guides, bearing units, couplings, supernuts, anti-backlash nuts

Howard W. Sams guide to satellite TV technology

Wind loading affects both the mount and the actuator. Acme Thread and Ball Screw Actuators An Acme thread actuator uses a threaded screw shaft that travels ...

Mechatronics, electronics in products and processes

18.6 Motor and ball screw Typically these linear actuators consist of an electric motor (eg a DC servomotor: see section 19.5.3) and a screw jack with a ...

Industrial Control Technology, A Handbook for Engineers and Researchers

Linear electric actuators are often used when tight tolerances are required. These electric actuators use an acme screw assembly or motor-driven ball screw ...

Proceedings of the 35th International MATADOR Conference, formerly the International Machine Tool Design and Research Conference

Nano-positioning Drive with Piezoelectric Actuator Integrated into Support Bearing Unit of Ball Screw A. Matsubara1, T. Fujita2, D. Kono3, N.Tanaka4 and ...